package com.migule.mymall.mallproduct.service.impl;

import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.migule.common.utils.PageUtils;
import com.migule.common.utils.Query;

import com.migule.mymall.mallproduct.dao.CategoryDao;
import com.migule.mymall.mallproduct.entity.CategoryEntity;
import com.migule.mymall.mallproduct.service.CategoryService;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1. 查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);
        //2.组装成tree
        //2.1找到所有以及分类: 一及分类没有父分类，所有的父分类都是零
        List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
                categoryEntity.getParentCid()==0).map((menu)->{
            menu.setChildren(getChildrens(menu,entities));
            return menu;
        }).sorted((menu1,menu2)->{
            return (menu1.getSort() == null?0:menu1.getSort())-(menu2.getSort() == null?0:menu2.getSort());
        }).collect(Collectors.toList());

        return level1Menus;
    }
    /**
     *
     * @param root 当前的那个父类
     * @param all 全部 category
     * @return
     */
    public List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all){
        List<CategoryEntity> children = all.stream().filter(categoryEntity ->{
            return categoryEntity.getParentCid().equals(root.getCatId());//当前菜单父id等于跟菜单id，这就是当前菜单的子菜单
        }).map(categoryEntity ->{//为当前菜单找子菜单
            categoryEntity.setChildren(getChildrens(categoryEntity,all));
            return categoryEntity;
        }).sorted((menu1,menu2)->{
            return (menu1.getSort() == null?0:menu1.getSort())-(menu2.getSort() == null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return children;
    }

}